My pricipal of calculation takes in to acount the total thickness of the spacer and where the inner shock mount is in relation to the top or bottom.

Then using double lift for what it is above and single lift for what it is below, I get real close to the actaul lift. Close enough for gubment work.

Where it gets a little complicated is moving the shock mount higher or lower inside the spacer. The higher inside the spacer you move it, the more single lift you'll get. The lower inside the more double lift you get. You can only lower it so far before the shock will jam on full compression.

The best way I can put it in an equation is...


XYPDQ x XYPDQ = XYPDQ squared

 

Jared, the forum is the same one I refered you to in your mechanical engineering thread.

Slopoke, I think this is a case where you made the equation fit your expected answer rather than letting the equation tell you the answer. The reason a 1" spacer gives twice the lift is because of the geometry of the suspension arms, not because of a change in preload. The lower A-arm is a lever. The shock is mounted in the middle of the lever. At one end of the lever is a pivot point and at the other end is the tire. Move the lever down 1" at the middle and you get twice the travel at the tire.

So back to the original question, the spring doesn't know whether the spacer is above or below the spring plate. You get the same amount of lift whether the spacer is above or below the plate.

Edit: I see you're in mechanical engineering sales. Are you a mechanical engineer? If so, do a free body diagram of the suspension system. If your not, have an engineer do one for you. Also, please define what the variables in your equation are.

 

No ME degree here but I did stay at a Holiday Inn Express last night. I understand what your saying but the fact is, depending on the amount the spacer sticks below and above the stock plate, it alters the amount of lift.

In theory your right but in practicality, the amoutn of lift differs by the amount of spacer above and below. It is NOT a true statement to say that a 2" spacer yields 2" of lift.
Ever design something that worked on paper and didn't quite cut it when you got it built or it needed tweaks you couldl't see in the design phase?

BTW: (in fear of sounding disrespectful and I don't wanna) How many types of spacers have you made? Those ones you showed in the pics? You have a better way of explaining in words than I do. This is why I keep saying to 'em...you'll know what I mean when you go to fabbin' 'em.

 

Pathagriums Theriumanumanum?

So, your sure?

The variables wuz just .... well, random variables. (hence the thinkin' devil hillbilly)

 

I agree. It should give more. According to Bamachem a 1.5" spacer gives a lift of 2.5" so 1.5/2.5=2/X, where X=the amount of lift. X=3.33" so a 2" spacer will give a lift of 3.3". This is because of the pythagorean theorem as you said.

 

I am trying to find coil spring spacers to fit my AWD 02 highlander to lift an inch or two at the most. Any ideas or help out there?